It is known that glycogen, a polysaccharide comprised of glucose and energetic reserve of living cells, is particularly abundant in yeast cells.
There are already known different processes for disintegration and treatment of yeast cells for the production of proteins, particularly recombinant ones, comprising the disintegration of said cells, the separation of the cellular debris, the recovery of the proteins and the purification of these latter.
Nevertheless, these known processes do not permit a preferential extraction of glycogens with high yield.
There are also known processes for the hydrolysis of yeast cells by thermal, enzymatic or chemical treatment, permitting producing yeast extracts for alimentary or therapeutic uses.
However, these known processes, often based on acid hydrolyses, lead to preparations in the form of hydrolysates containing together the proteins and the polysaccharides of yeast, and cannot supply yeast extracts specifically enriched in glycogens.
It is known moreover to extract glycogens from marine bacteria, and to subject these latter to a thermal and chemical treatment, to a trichloroacetic acid precipitation and to consecutive precipitations with ethanol.
These extractions, carried out on a laboratory scale, have only for their object to permit the analysis of the structure and the composition of the soluble glycogens and are not applicable other than to the specific type of cells in question, and are not applicable to cells having more resistant walls.
Finally, there already exist processes for the permeabilization of the cell walls of yeast and for the hydrolysis of the intracellular glycogens in glucose, so as to measure the amount present, these processes however cannot ensure extraction of the glycogen as such, particularly in an unhydrolyzed form.